Two-Dimensional Millimeter-Wave Beam-Switching Antenna Using an ELC Meta-Lens

Abstract

A 2-D beam switching dipole antenna working at 60 GHz is proposed. To realize this, a folded electric-field coupled (ELC) resonator is designed to achieve a high-refractive-index medium in the band of 57–64 GHz. By integrating an array of ELC resonators in the off-center of a printed dipole antenna in the E- and H-planes forming high-refractive-index medium lenses (metalenses) in each plane, the main beam direction is manipulated to generate 2-D beam switching at 60 GHz. In the final configuration, six slabs each containing three folded ELC inclusions are incorporated vertically in front of the dipole antenna in the azimuth plane to tilt the radiation beam by 25° in the H-plane. In addition, a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2\times5$ </tex-math></inline-formula> array of folded ELC resonators is added into the elevation plane of the antenna substrate to deflect the radiated beam in the E-plane by 20°. The measurement results confirm that the radiated beam is tilted by 25° and 20° in the H- and E-planes, respectively, over a frequency band of 57–64 GHz. The measured antenna gain is 10.7 dBi at 61 GHz, the measured reflection coefficient is below −10 dB over 57–64 GHz, and the measured radiation efficiency of the antenna is 82% at 60 GHz.